Transmission-band-operating device



April 5 192.7. 1,623,312

A M; HQFFMAN TRANSMISSION BAND`OPEEIIATING DEVICE AFiled oct. 1s, 1924 IVIIVCHAEL HOFFMAN, OF LOS ANGELES, CALIFORNIA.

TRANSMISSION-BAND-OPERATING DEVICE.

Application filed October 13,1924. Serial No. 743,260.

' This invention relates to an arrangement for facilitating the removal of band-s such as are used for clutching purposes in certain classes of transmissions and the object of the invention is to provide a simple, inexpensive and convenient means by which band reL placements may be made quickly and withoutthe experience of the skilled.

The main purpose of the present provision is to obviate alterations, fitting and adjustment of old parts and to provide an installation which constitutes an entire and complete substitution of a part or of parts in use ordinarily with transmissions employing bands; which may be set in .position without dis` mantling the housing, and which will be automatically locked and held in position of adjustment.

Other objects will appear hereinafter in connection with the accompanying drawing, which illustrates a selected embodiment of the invention and in which- Fig. 1 is a sectional front view showing a transmission band as used in connection Vwith an automobile transmission, and means embodying this invention for moving the band.

Fig. 2 is a fragmentary section showing one end of the band and the means co-operating with the band during the operation of same.

Fig. 3 is a section on line 3-3-Fig- 1, and

Fig. 4 is a perspective view of my improvement. Y

The invention is applicable, as stated, to a .certain class of motor vehicle which uses transmission bands, and thoseparts with which the present invention is associated ben ing of standard, Well-known construction, will be referred to only generally.

The transmission housing 1, is provided with a cover 2, removable for thepurpose of facilitating access to the band 3, which is contained within the housing 1 and is operable relatively to the gear drum 4, as eX- plained later. The housing is provided with the usual bearings 5 and 6, the former for a cam shaft 7, and thelatter for a band engaging and adjusting member 8 having a longitudinal bore 8, for purposes appearing presently. Theshaft 7 carries on one end a cam section 9 and at the other end outside the housing 1 an actuating pedal 10, by

which the cam section 9, in co-operation with the cam section 9 formed on the bearing 5,

is moved in a horizontal direction, for coni` tracting the band 3 and clutching the drum 4. The` band 3 referred to is of usual construction and type, vand at its respective ends is provided with slotted members 11 and 12, the latter being adjacent to and held f againstr the adjusting member 8. Between the cam section 9 and the member 11 of the band 3 is interposed the cup or cupped mem! ber 13 formed on or carried by a shaft 14', this cup or cupped member 13 fitting over the end of said cam section 9 and being securely held iii-position at this engaging' end by the pressure exerted `between the slotted members11 and 12 of the band by a helical spring 15 coiled about .said shaft 14 and bearing at one end against the inside of the member 11 of the band 3, andat thek other end against the inside of the band member 12, with a constant tendency to force Y into a removable one, without disturbing the.

housing. The operation of the band 3 is entirely identical with the operation fol-y lowed in otherinstance. Thus, when the pedal 10 is moved to actuating position, the cam section 9 with the lshaft 7 is caused to move in a horizontal plane. This cam section 9 being engaged into the hollow cup portion 13 of the shaft 14, transfers its mo tion to it, and in turn to the slotted member 11 of the'b'and 3, which, on being moved toward its companionend 12, clutches the gear drum 4. rIhe return to normal, disengaging position of the band and its complementary part is effected by the spring 15.

In order to replace a band or remove it from the housing, the member 8 is disconnected from the bearing 6, and the end 16 of the shaft14 being fre-e, the shaft 14, may

be readily lifted out of the slotted members 11 and 12, without disturbing the housing 1, other than removing the cover 2 thereof.

I am aware that there have been devised' ,eraan and marketed devices comprising substitutions for the shaft usual in the article as manufactured, but they comprise in their essential composition a part or parts of the old elements to bev substituted for the new,

andV hence require alteration, or other meiohanical attention, which takes the work oi"V Vreplacement outside the range of the uni skilled, butI am not aware of the Vprovision 'j fof a single mean-s, for the purposes dened i0 Y and claimed. f

' g VVhatIclaim, is: i

l.V In a transmission, .the combination With ya drum, theV band surrounding the drum, and having slotted members at its respective ends, a means for actuating one of 'said slotted members toward the other for tightening the band around said drum, comprising a cam section, a pedal to operate said l cam section, and a shaft, extended through 2.7111 a transmission includingthe drum,` the band surrounding the drum and having` slotted members at its respective ends, a means for actuating one of the slotted inembers of said band toward the other to grip the drum, comprising a cam section, apedal to operate said cam section and a shaft eX- L tended through the slotted members of said band, said sha-tt having a cupped endto lit Y over the end ot said cam section and between said cam section and one `of the slotted members. Y l

In testimony whereof I have set my hand. MICHAEL HGFFMAN. 

